Since a synthetic resin is degraded by light and not endurable for a long-term use, stabilization by adding a hindered amine compound or an ultraviolet absorber is prevailing.
Various hindered amine compounds, in addition to the exemplified compounds disclosed in the following Patent Documents 1 to 5, have been proposed.
Similarly, various ultraviolet absorbers, such as benzotriazole type ultraviolet absorbers, benzophenone type ultraviolet absorbers, and benzoate type ultraviolet absorbers, have been known. For example, Patent Document 6 has proposed phenyl benzoate and alkyl benzoate as benzoate type ultraviolet absorbers.
Furthermore, it has been broadly known that a highly stabilized resin composition can be obtained by a combined use of additives. For example, the following Patent Documents 7 to 11 have proposed a combined use of a certain hindered amine compound and a benzoate type ultraviolet absorber.    Patent Document 1: Japanese Examined Patent Application Publication No. 46-42618    Patent Document 2: Japanese Unexamined Patent Application Publication No. 48-65180    Patent Document 3: Japanese Unexamined Patent Application Publication No. 59-62651    Patent Document 4: Japanese Unexamined Patent Application Publication No. 1-113368    Patent Document 5: Japanese Unexamined Patent Application Publication No. 2-166138    Patent Document 6: Japanese Examined Patent Application Publication No. 41-565    Patent Document 7: Japanese Unexamined Patent Application Publication No. 11-310667    Patent Document 8: Japanese Unexamined Patent Application Publication No. 11-106577    Patent Document 9: Japanese Unexamined Patent Application Publication No. 2000-136271    Patent Document 10: Japanese Unexamined Patent Application Publication No. 2000-159945    Patent Document 11: Japanese Unexamined Patent Application Publication No. 2004-210987    Patent Document 11: Japanese Unexamined Patent Application Publication No. 2005-054105